Merge tag 'large-extent-counters-v9' of https://github.com/chandanr/linux into xfs-5.19-for-next
xfs: Large extent counters The commit xfs: fix inode fork extent count overflow (3f8a4f1d) mentions that 10 billion data fork extents should be possible to create. However the corresponding on-disk field has a signed 32-bit type. Hence this patchset extends the per-inode data fork extent counter to 64 bits (out of which 48 bits are used to store the extent count). Also, XFS has an attribute fork extent counter which is 16 bits wide. A workload that, 1. Creates 1 million 255-byte sized xattrs, 2. Deletes 50% of these xattrs in an alternating manner, 3. Tries to insert 400,000 new 255-byte sized xattrs causes the xattr extent counter to overflow. Dave tells me that there are instances where a single file has more than 100 million hardlinks. With parent pointers being stored in xattrs, we will overflow the signed 16-bits wide attribute extent counter when large number of hard...
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